After a day waiting for a phone call from her missing daughter, Charlotte Campbell learned the worst. She rang police , hospitals, hotels, but was told to wait. She took to Facebook and Twitter to share her daughter's photo and made impassioned pleas for help on television and radio.

But on Tuesday night Ms Campbell knew her 15-year-old daughter Olivia would never return home. Olivia was identified by her mother as one of the 22 victims of the suicide bombing at Manchester Arena, where US pop star Ariana Grande had played to nearly 20,000 people.

"Just know that there's an entire world out here that is grieving for your loss," Peggy Jones wrote. Also among the victims of the blast were eight-year-old Saffie Rose Roussos and 18-year-old Georgina Callander.

John Atkinson, 26, was also been named among the dead on Wednesday by family and friends on social media.

On Wednesday evening, the Polish foreign minister confirmed couple Marcin and Angelika Klis had also been killed in the attack.

He said the Polish couple was waiting at the concert to pick up their children when they were caught up in the explosion.

Olivia Campbell became one of the most high-profile missing victims, after her mother's desperate pleas for help on social media caught the attention of people around the world. Ms Campbell's posts were shared tens of thousands of times by people across the world, with Olivia's name trending on Twitter.

"It's the most horrible feeling ever, to know that your daughter's there and you can't find her and you don't know if she's dead or alive," a tearful Ms Campbell told US news network CNN.

"I don't know how people can do this to innocent children."

The Manchester mother broke down in tears on ITV's Good Morning Britain just hours before she shared the news of her daughter's death.

"All I know is she was at the Manchester Arena with her friend watching Ariana Grande and she's not turned up yet," she said.

"I can't get through to her. I've called the hospitals, I've called all the places, the hotels where people say that children have been taken. I've called the police. There's no news, I've just got to wait. I'm waiting at home just in case she turns up here." Ms Campbell told the BBC she last had contact with her daughter shortly before Grande took to the stage.

"She was at the concert, she'd just seen the support act and said she was having an amazing time and thanking me for letting her go," she said.

"She was with her friend, Adam. Adam was found about half an hour ago – he's in hospital – but Olivia's not been found yet ... I'm just hearing nothing." Many parents were still waiting on Wednesday, more than 24 hours after the terror attack, to find out if their children were among the dead or injured, sharing photos on Facebook and Twitter with the #MissingInManchester hashtag.

Marcin and Angelika Klis have been confirmed as two more victims of the bombing in Manchester. Polish couple Marc in and Angelika Klis had gone to Manchester Arena to collect their daughters after the concert on Monday night.

In the hours after the bombing, their daughter Alex tried to desperately find them, writing on Facebook: "Anyone who is in any safe place or hospital in Manchester, if anyone comes across my parents please please let me know as they've been missing ever since the attack."

Poland's Foreign Minister Witold Waszczykowski told a Polish radio station, "The parents came after the concert to collect their daughters and unfortunately we have information tha t they are dead. The children are safe."

John Atkinson, a pop music fan from Radcliffe, was reportedly leaving the venue when he was fatally injured by the blast.

Tributes for Mr Atkinson were paid by the local adult dance troupe, Freak Dance Radcliffe, for whom the 26-year-old danced competitively.

"Today is an amazingly sad day! 'We have lost a member of our dance family," read the group's message onFacebook.

Mr Atkinson was described as a "happy gentle person" and a "real pleasure to teach". "He was a true friend, not just to our staff but many of the parents and students from the school. Our thoughts are with the family at the very sad and hard time!" Other friends posted their condolences online, saying Mr Atkinson was an "amazing young man" and a "beautiful so ul".

Facebook friend Gill Corless, posted a photo of a candle, with the message: "My candle lit for John Atkinson and the 21 others who lost their lives in the evil senseless attack in Manchester, shine bright in the sky tonight john."

On Tuesday night, candlelit vigils were held in Manchester and in the village of Tarleton and Hesketh Bank for Saffie and Georgina.

Flowers and messages were laid in Tarleton's Marks Square. "As darkness has fallen on our little village tonight the candles are burning brightly for [Georgina] and Saffie, young Angels in the sky and all the other victims of this atrocity," one local wrote on Facebook.

"Watching [Georgina's] mum and family and little children cry and hug each other in bewilderment at the vigil was heartbreaking. So Proud of Tarleton folk standing united in grief." Georgina Callander's family thanked the community for their support.

"Thank you all who attended the vigil, it was amazing couldn't of asked for anything more, from all the Callanders," Daniel Callander wrote on Facebook. with The Telegraph.